Currently, the AF_XDP PMD attaches its XDP program using a fixed set of flags, defaulting to `XDP_FLAGS_UPDATE_IF_NOEXIST`. This lacks flexibility for users who might need to explicitly control the XDP mode based on their specific hardware capabilities or performance requirements.
This patch introduces a new vdev argument, `mode`, for the `net_af_xdp` PMD. This argument allows users to explicitly specify the desired XDP program attachment mode: `drv` (XDP_FLAGS_DRV_MODE), `skb` (XDP_FLAGS_SKB_MODE), `hw` (XDP_FLAGS_HW_MODE). (If needed more can be added) This change provides greater control and flexibility for users to fine-tune AF_XDP behavior, enabling them to leverage native driver or hardware offload capabilities when available, or fall back to generic SKB mode for broader compatibility. Signed-off-by: Shivaji Kant <shivajik...@google.com> --- Changes in v2: The attach mode flag was intended to be per device flag. So making it part of the pmd_internals struct. --- Changes in v3 Fix the build error for cases without RTE_NET_AF_XDP_LIBBPF_XDP_ATTACH --- Changes in v4 Add check for invalid path argument return. --- drivers/net/af_xdp/rte_eth_af_xdp.c | 77 ++++++++++++++++++++++++----- 1 file changed, 64 insertions(+), 13 deletions(-) diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c b/drivers/net/af_xdp/rte_eth_af_xdp.c index 5f65850a27..9858ac24b2 100644 --- a/drivers/net/af_xdp/rte_eth_af_xdp.c +++ b/drivers/net/af_xdp/rte_eth_af_xdp.c @@ -169,6 +169,7 @@ struct pmd_internals { int queue_cnt; int max_queue_cnt; int configured_queue_cnt; + uint mode_flag; bool shared_umem; char prog_path[PATH_MAX]; bool custom_prog_configured; @@ -198,6 +199,26 @@ struct pmd_process_private { #define ETH_AF_XDP_USE_CNI_ARG "use_cni" #define ETH_AF_XDP_USE_PINNED_MAP_ARG "use_pinned_map" #define ETH_AF_XDP_DP_PATH_ARG "dp_path" +#define ETH_AF_XDP_MODE_ARG "mode" + +/* Define different modes for af_xdp prog to attach */ +#define ETH_AF_XDP_DRV_MODE_ARG "drv" +#define ETH_AF_XDP_SKB_MODE_ARG "skb" +#define ETH_AF_XDP_HW_MODE_ARG "hw" +#define ETH_AF_XDP_NUM_MODE_ARG 3 + +static const char * const mode_arguments[] = { + ETH_AF_XDP_DRV_MODE_ARG, + ETH_AF_XDP_SKB_MODE_ARG, + ETH_AF_XDP_HW_MODE_ARG, + NULL +}; + +static const unsigned int mode_flags[] = { + XDP_FLAGS_DRV_MODE, + XDP_FLAGS_SKB_MODE, + XDP_FLAGS_HW_MODE +}; static const char * const valid_arguments[] = { ETH_AF_XDP_IFACE_ARG, @@ -210,6 +231,7 @@ static const char * const valid_arguments[] = { ETH_AF_XDP_USE_CNI_ARG, ETH_AF_XDP_USE_PINNED_MAP_ARG, ETH_AF_XDP_DP_PATH_ARG, + ETH_AF_XDP_MODE_ARG, NULL }; @@ -950,14 +972,14 @@ remove_xdp_program(struct pmd_internals *internals) uint32_t curr_prog_id = 0; int ret; - ret = bpf_xdp_query_id(internals->if_index, XDP_FLAGS_UPDATE_IF_NOEXIST, + ret = bpf_xdp_query_id(internals->if_index, internals->mode_flag, &curr_prog_id); if (ret != 0) { AF_XDP_LOG_LINE(ERR, "bpf_xdp_query_id failed"); return ret; } - ret = bpf_xdp_detach(internals->if_index, XDP_FLAGS_UPDATE_IF_NOEXIST, + ret = bpf_xdp_detach(internals->if_index, internals->mode_flag, NULL); if (ret != 0) AF_XDP_LOG_LINE(ERR, "bpf_xdp_detach failed"); @@ -978,14 +1000,14 @@ remove_xdp_program(struct pmd_internals *internals) int ret; ret = bpf_get_link_xdp_id(internals->if_index, &curr_prog_id, - XDP_FLAGS_UPDATE_IF_NOEXIST); + internals->mode_flag); if (ret != 0) { AF_XDP_LOG_LINE(ERR, "bpf_get_link_xdp_id failed"); return ret; } ret = bpf_set_link_xdp_fd(internals->if_index, -1, - XDP_FLAGS_UPDATE_IF_NOEXIST); + internals->mode_flag); if (ret != 0) AF_XDP_LOG_LINE(ERR, "bpf_set_link_xdp_fd failed"); return ret; @@ -1305,7 +1327,7 @@ get_pinned_map(const char *dp_path, int *map_fd) } static int -load_custom_xdp_prog(const char *prog_path, int if_index, struct bpf_map **map) +load_custom_xdp_prog(const char *prog_path, int if_index, struct bpf_map **map, uint mode_flag) { int ret, prog_fd; struct bpf_object *obj; @@ -1328,7 +1350,7 @@ load_custom_xdp_prog(const char *prog_path, int if_index, struct bpf_map **map) /* Link the program with the given network device */ ret = link_xdp_prog_with_dev(if_index, prog_fd, - XDP_FLAGS_UPDATE_IF_NOEXIST); + mode_flag); if (ret) { AF_XDP_LOG_LINE(ERR, "Failed to set prog fd %d on interface", prog_fd); @@ -1679,7 +1701,7 @@ xsk_configure(struct pmd_internals *internals, struct pkt_rx_queue *rxq, cfg.rx_size = ring_size; cfg.tx_size = ring_size; cfg.libbpf_flags = 0; - cfg.xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST; + cfg.xdp_flags = internals->mode_flag; cfg.bind_flags = 0; /* Force AF_XDP socket into copy mode when users want it */ @@ -1698,7 +1720,7 @@ xsk_configure(struct pmd_internals *internals, struct pkt_rx_queue *rxq, if (!internals->custom_prog_configured) { ret = load_custom_xdp_prog(internals->prog_path, internals->if_index, - &internals->map); + &internals->map, internals->mode_flag); if (ret) { AF_XDP_LOG_LINE(ERR, "Failed to load custom XDP program %s", internals->prog_path); @@ -2017,6 +2039,25 @@ parse_name_arg(const char *key __rte_unused, return 0; } +/** parse name argument */ +static int +parse_mode_arg(const char *key __rte_unused, + const char *value, void *extra_args) +{ + unsigned int *mode = extra_args; + unsigned int i; + + for (i = 0; i < ETH_AF_XDP_NUM_MODE_ARG; i++) { + if (strcmp(value, mode_arguments[i]) == 0) { + *mode |= mode_flags[i]; + return 0; + } + } + + AF_XDP_LOG_LINE(ERR, "Invalid af_xdp mode, choose correct mode to attach af_xdp program."); + return -EINVAL; +} + /** parse xdp prog argument */ static int parse_prog_arg(const char *key __rte_unused, @@ -2094,7 +2135,7 @@ static int parse_parameters(struct rte_kvargs *kvlist, char *if_name, int *start_queue, int *queue_cnt, int *shared_umem, char *prog_path, int *busy_budget, int *force_copy, int *use_cni, - int *use_pinned_map, char *dp_path) + int *use_pinned_map, char *dp_path, uint *xdp_mode) { int ret; @@ -2147,6 +2188,13 @@ parse_parameters(struct rte_kvargs *kvlist, char *if_name, int *start_queue, ret = rte_kvargs_process(kvlist, ETH_AF_XDP_DP_PATH_ARG, &parse_prog_arg, dp_path); + + if (ret < 0) + goto free_kvlist; + + ret = rte_kvargs_process(kvlist, ETH_AF_XDP_MODE_ARG, + &parse_mode_arg, xdp_mode); + if (ret < 0) goto free_kvlist; @@ -2189,7 +2237,7 @@ static struct rte_eth_dev * init_internals(struct rte_vdev_device *dev, const char *if_name, int start_queue_idx, int queue_cnt, int shared_umem, const char *prog_path, int busy_budget, int force_copy, - int use_cni, int use_pinned_map, const char *dp_path) + int use_cni, int use_pinned_map, const char *dp_path, uint xdp_mode) { const char *name = rte_vdev_device_name(dev); const unsigned int numa_node = dev->device.numa_node; @@ -2220,6 +2268,7 @@ init_internals(struct rte_vdev_device *dev, const char *if_name, internals->force_copy = force_copy; internals->use_cni = use_cni; internals->use_pinned_map = use_pinned_map; + internals->mode_flag = XDP_FLAGS_UPDATE_IF_NOEXIST | xdp_mode; strlcpy(internals->dp_path, dp_path, PATH_MAX); if (xdp_get_channels_info(if_name, &internals->max_queue_cnt, @@ -2412,6 +2461,7 @@ rte_pmd_af_xdp_probe(struct rte_vdev_device *dev) int force_copy = 0; int use_cni = 0; int use_pinned_map = 0; + uint xdp_mode = 0; char dp_path[PATH_MAX] = {'\0'}; struct rte_eth_dev *eth_dev = NULL; const char *name = rte_vdev_device_name(dev); @@ -2456,7 +2506,7 @@ rte_pmd_af_xdp_probe(struct rte_vdev_device *dev) if (parse_parameters(kvlist, if_name, &xsk_start_queue_idx, &xsk_queue_cnt, &shared_umem, prog_path, &busy_budget, &force_copy, &use_cni, &use_pinned_map, - dp_path) < 0) { + dp_path, &xdp_mode) < 0) { AF_XDP_LOG_LINE(ERR, "Invalid kvargs value"); return -EINVAL; } @@ -2524,7 +2574,7 @@ rte_pmd_af_xdp_probe(struct rte_vdev_device *dev) eth_dev = init_internals(dev, if_name, xsk_start_queue_idx, xsk_queue_cnt, shared_umem, prog_path, busy_budget, force_copy, use_cni, use_pinned_map, - dp_path); + dp_path, xdp_mode); if (eth_dev == NULL) { AF_XDP_LOG_LINE(ERR, "Failed to init internals"); return -1; @@ -2587,4 +2637,5 @@ RTE_PMD_REGISTER_PARAM_STRING(net_af_xdp, "force_copy=<int> " "use_cni=<int> " "use_pinned_map=<int> " - "dp_path=<string> "); + "dp_path=<string> " + "mode=<string> "); -- 2.50.1.552.g942d659e1b-goog